i've heard diesel and aluminum dont mix well and it can make aluminum brittle. is this true. i already had one very brittle alum. fitting break going into my VP44 and i dont wanna put another anodized alum fitting on it and have it break dont and fall apart in a few years.

 

Use Stainless Steel.

 

IP case\housing, filter cannister, etc, is aluminum - aluminum doesn't survive bending\pushing\pulling\flexing\vibration\etc stresses, so not too good for fitting\piping where those might be encountered.

 

I've been running AN fittings on my truck for 3 years now with no issues whatsoever.

 

went ahead and got the -8AN to 12mmx1.5 adapter in anodized alum because nobody but Earl's makes one. trucks seems to run ok with the little 3/8" line and banjo bolt temporary fix...but i want my high flow BIG stuff back on there.

 

I've always firgured diesel an aluminium are ok together. I've been told before that copper and diesel don't mix well. Think about it for a second, your diesel fuel is hauled in tankers that are made from aluminium. You should be ok with aluminium fittings.